Compare dates between 2 different rows and columns

Question

I'm having problems figuring this out.  Here is an example table:
What I need to be able to find is any records where the Discontinue_Date is greater than the Effective_Date on the next row for a given Customer ID and Part_ID.  This is a customer pricing table so the Discontinue_Date of row 53 for example should never
be greater than the Effective_Date of row 54130, these are the records I'm looking to find.  So I'm looking for a SELECT query that would look for any records where this is true.  Obviously the last Discontinue_Date row for a Customer_ID will not
have a next row so I wouldn't want to return that. 
Let me know if anyone has any ideas or if more clarification is needed, I've been struggling with how to get started on this!!
Thanks very much in advance!
JIM

Answer 1

>> I'm having problems figuring this out. Here is an example table: <<
NO! Please post DDL, so that people do not have to guess what the keys, constraints, Declarative Referential Integrity, data types, etc. in your schema are. Learn how to follow ISO-11179 data element naming conventions and formatting rules. Temporal data
should use ISO-8601 formats. Code should be in Standard SQL as much as possible and not local dialect. 
This is minimal polite behavior on SQL forums. You pasted a colored picture that we have to transcribe into DDL to do your job for you. But you also do not know basic terminology! 
Rows are not records, since tables are sets, there is no “next row” concept, rows do not have physical row numbers, etc.  Your mindset is still in a spreadsheet and not RDBMS. 
>> What I need to be able to find is any records [sic] where the discontinuation_date is greater than the effective_date on the next row for a given customer_id and part_id. <<
Why not prevent bad data instead of trying to kludge and report it after the fact? 
 Consider this self-reference trick to prevent gaps in a timeline of events:
CREATE TABLE Events
(event_id CHAR(10) NOT NULL,
previous_event_end_date DATE NOT NULL
CONSTRAINT Chained_Dates
REFERENCES Events (event_end_date),
event_start_date DATE NOT NULL,
event_end_date DATE UNIQUE, -- null means event in progress
PRIMARY KEY (event_id, event_start_date),
CONSTRAINT Event_Order_Valid
CHECK (event_start_date <= event_end_date),
CONSTRAINT Chained_Dates 
CHECK (DATEADD(DAY, 1, previous_event_end_date) = event_start_date).
<< other stuff for this event >>
-- disable the Chained_Dates constraint
ALTER TABLE Events NOCHECK CONSTRAINT Chained_Dates
-- insert a starter row
INSERT INTO Events(event_id, previous_event_end_date, event_start_date, event_end_date)
VALUES ('Foo Fest', '2010-01-01', '2010-01-02', '2010-01-05');
-- enable the constraint in the table
ALTER TABLE Events CHECK CONSTRAINT Chained_Dates
-- this works
INSERT INTO Events(event_id, previous_event_end_date, event_start_date, event_end_date)
VALUES ('Glob Week', '2010-01-05', '2010-01-06', '2010-01-10');
-- this fails
INSERT INTO Events(event_id, previous_event_end_date, event_start_date, event_end_date)
VALUES ('Snoob', '2010-01-09', '2010-01-11', '2010-01-15'); 
Since you did not write DDL for us, you can use this idiom to get a working schema. 
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